dbx500-prcmu.c

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/*
 * Copyright (C) ST-Ericsson SA 2010
 *
 * License Terms: GNU General Public License v2
 * Authors: Sundar Iyer <[email protected]> for ST-Ericsson
 *          Bengt Jonsson <[email protected]> for ST-Ericsson
 *
 * UX500 common part of Power domain regulators
 */

#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/regulator/driver.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/slab.h>

#include "dbx500-prcmu.h"

/*
 * power state reference count
 */
static int power_state_active_cnt; /* will initialize to zero */
static DEFINE_SPINLOCK(power_state_active_lock);

int power_state_active_get(void)
{
    unsigned long flags;
    int cnt;

    spin_lock_irqsave(&power_state_active_lock, flags);
    cnt = power_state_active_cnt;
    spin_unlock_irqrestore(&power_state_active_lock, flags);

    return cnt;
}

void power_state_active_enable(void)
{
    unsigned long flags;

    spin_lock_irqsave(&power_state_active_lock, flags);
    power_state_active_cnt++;
    spin_unlock_irqrestore(&power_state_active_lock, flags);
}

int power_state_active_disable(void)
{
    int ret = 0;
    unsigned long flags;

    spin_lock_irqsave(&power_state_active_lock, flags);
    if (power_state_active_cnt <= 0) {
        pr_err("power state: unbalanced enable/disable calls\n");
        ret = -EINVAL;
        goto out;
    }

    power_state_active_cnt--;
out:
    spin_unlock_irqrestore(&power_state_active_lock, flags);
    return ret;
}

#ifdef CONFIG_REGULATOR_DEBUG

static struct ux500_regulator_debug {
    struct dentry *dir;
    struct dentry *status_file;
    struct dentry *power_state_cnt_file;
    struct dbx500_regulator_info *regulator_array;
    int num_regulators;
    u8 *state_before_suspend;
    u8 *state_after_suspend;
} rdebug;

void ux500_regulator_suspend_debug(void)
{
    int i;
    for (i = 0; i < rdebug.num_regulators; i++)
        rdebug.state_before_suspend[i] =
            rdebug.regulator_array[i].is_enabled;
}

void ux500_regulator_resume_debug(void)
{
    int i;
    for (i = 0; i < rdebug.num_regulators; i++)
        rdebug.state_after_suspend[i] =
            rdebug.regulator_array[i].is_enabled;
}

static int ux500_regulator_power_state_cnt_print(struct seq_file *s, void *p)
{
    struct device *dev = s->private;
    int err;

    /* print power state count */
    err = seq_printf(s, "ux500-regulator power state count: %i\n",
        power_state_active_get());
    if (err < 0)
        dev_err(dev, "seq_printf overflow\n");

    return 0;
}

static int ux500_regulator_power_state_cnt_open(struct inode *inode,
    struct file *file)
{
    return single_open(file, ux500_regulator_power_state_cnt_print,
        inode->i_private);
}

static const struct file_operations ux500_regulator_power_state_cnt_fops = {
    .open = ux500_regulator_power_state_cnt_open,
    .read = seq_read,
    .llseek = seq_lseek,
    .release = single_release,
    .owner = THIS_MODULE,
};

static int ux500_regulator_status_print(struct seq_file *s, void *p)
{
    struct device *dev = s->private;
    int err;
    int i;

    /* print dump header */
    err = seq_printf(s, "ux500-regulator status:\n");
    if (err < 0)
        dev_err(dev, "seq_printf overflow\n");

    err = seq_printf(s, "%31s : %8s : %8s\n", "current",
        "before", "after");
    if (err < 0)
        dev_err(dev, "seq_printf overflow\n");

    for (i = 0; i < rdebug.num_regulators; i++) {
        struct dbx500_regulator_info *info;
        /* Access per-regulator data */
        info = &rdebug.regulator_array[i];

        /* print status */
        err = seq_printf(s, "%20s : %8s : %8s : %8s\n", info->desc.name,
            info->is_enabled ? "enabled" : "disabled",
            rdebug.state_before_suspend[i] ? "enabled" : "disabled",
            rdebug.state_after_suspend[i] ? "enabled" : "disabled");
        if (err < 0)
            dev_err(dev, "seq_printf overflow\n");
    }

    return 0;
}

static int ux500_regulator_status_open(struct inode *inode, struct file *file)
{
    return single_open(file, ux500_regulator_status_print,
        inode->i_private);
}

static const struct file_operations ux500_regulator_status_fops = {
    .open = ux500_regulator_status_open,
    .read = seq_read,
    .llseek = seq_lseek,
    .release = single_release,
    .owner = THIS_MODULE,
};

int __attribute__((weak)) dbx500_regulator_testcase(
    struct dbx500_regulator_info *regulator_info,
    int num_regulators)
{
    return 0;
}

int __devinit
ux500_regulator_debug_init(struct platform_device *pdev,
    struct dbx500_regulator_info *regulator_info,
    int num_regulators)
{
    /* create directory */
    rdebug.dir = debugfs_create_dir("ux500-regulator", NULL);
    if (!rdebug.dir)
        goto exit_no_debugfs;

    /* create "status" file */
    rdebug.status_file = debugfs_create_file("status",
        S_IRUGO, rdebug.dir, &pdev->dev,
        &ux500_regulator_status_fops);
    if (!rdebug.status_file)
        goto exit_destroy_dir;

    /* create "power-state-count" file */
    rdebug.power_state_cnt_file = debugfs_create_file("power-state-count",
        S_IRUGO, rdebug.dir, &pdev->dev,
        &ux500_regulator_power_state_cnt_fops);
    if (!rdebug.power_state_cnt_file)
        goto exit_destroy_status;

    rdebug.regulator_array = regulator_info;
    rdebug.num_regulators = num_regulators;

    rdebug.state_before_suspend = kzalloc(num_regulators, GFP_KERNEL);
    if (!rdebug.state_before_suspend) {
        dev_err(&pdev->dev,
            "could not allocate memory for saving state\n");
        goto exit_destroy_power_state;
    }

    rdebug.state_after_suspend = kzalloc(num_regulators, GFP_KERNEL);
    if (!rdebug.state_after_suspend) {
        dev_err(&pdev->dev,
            "could not allocate memory for saving state\n");
        goto exit_free;
    }

    dbx500_regulator_testcase(regulator_info, num_regulators);
    return 0;

exit_free:
    kfree(rdebug.state_before_suspend);
exit_destroy_power_state:
    debugfs_remove(rdebug.power_state_cnt_file);
exit_destroy_status:
    debugfs_remove(rdebug.status_file);
exit_destroy_dir:
    debugfs_remove(rdebug.dir);
exit_no_debugfs:
    dev_err(&pdev->dev, "failed to create debugfs entries.\n");
    return -ENOMEM;
}

int __devexit ux500_regulator_debug_exit(void)
{
    debugfs_remove_recursive(rdebug.dir);
    kfree(rdebug.state_after_suspend);
    kfree(rdebug.state_before_suspend);

    return 0;
}
#endif